[ksrhee]

For me, both are good programs, but I settled with OF for a variety of reasons:

1. OF is a lot more powerful and flexible than Things. I can customize my views to suit my needs using perspectives. My observation of folks who prefer Things over OF citing the ease of use and simplicity probably haven't utilized the perspective capability to fullest in OF. There are certain limitations in things that are hugh constraints for me in my workflow such as not being able to assign task to a project and schedule it at the same time and a few others mentioned by others that I won't repeat.
2. Data entry and organization is much easier/faster in OF. Why spend time entering information when the key is getting things done, not writing/planning things? I've tried many other programs but there is nothing I found comparable when it comes to entering information into the program.
3. Iphone integration is much more smoother and versatile (multiple methods of synching). Now with the latest version, entering a new task is also fast.
4. Superb integration with Mail (MailTag) and other programs. Another reason why it's so much easier to manage information . . .

As far as using tags (yes I did create a beautiful system in Things when I was trying it out), but I realized that I wasn't using it as much. In fact, it got so complicated (with hierarchy and multiple tags) that I was spending more time entering/figure things out than doing the actual work. I'm not saying OF is perfect right now, but more complicated tagging system, less useful it got for me. Of course, YMMV.

I think there might be a few more, but these are my main reasons why I keep using OF even after trying many other task/life management programs.